Sometimes these remains can identify the type of

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carnivorous, herbivorous or omnivorous animal. Sometimes these remains can identify the type of animal or plant that was eaten. Dinosaur footprint cast Fossilized footprints are trace fossils. Trace fossils can be borings and other evidence of ancient animal activities preserved in stone. This is probably a small bipedal theropod, which lived during the Triassic, from The New England area.
10 Big Box with AMMONITES AND NAUTILUSPaleontologists often compare extinct organisms with extant relatives to better understand their relationships. The living nautilus, for example, is a close cousin to an extinct group known as ammonites. Ammonites had a similar shell, with internal chambers for buoyancy. The boundary between the internal chamber and the outer shell is called a “suture” and is the primary identification feature. As a general rule, sutures became more complicated over time. Ammonites went extinct at the end of the Cretaceous about 65 million years ago, the same time as the dinosaurs. NAUTILUSA nautilus swims using jet propulsionit expels water from its mantle cavity through a siphon located near its head. By adjusting the direction of the siphon, a nautilus can swim forward, backward or sideways. A native of the tropical Pacific, this cousin of the octopus is a living link with the pastlittle changed for more than 150 million years. A newly hatched nautilus wears a shell divided into four small chambers. As a nautilus grows, it gains more living space by building new chambers connected to the old ones; adult shells have 30 chambers. To control its buoyancy, a nautilus pumps fluids in and out its shell chambers. AMMONITESAmmonite(ammonis cornua"horns of Ammon" because the shell is shaped like the ram’s horns typically worn by the Egyptian god Ammon)Ammonites resemble the living nautilus, but are more closely related to other cephalopods such as octopi, squid and cuttlefish. Ammonite shells contain internal chambers for buoyancy, connected by a siphuncle or long tube. The boundary between the internal chamber and the outer shell is called a “suture” and is the primary identification feature. As ageneral rule, the sutures became more complicated over time making ammonites an excellent “index fossil” which means that certain species of ammonite are associated with specific types of rock layers and thereby specific geological time periods. Ammonites went extinct at the end of the Cretaceous about 65 million years ago, the same time as the dinosaursBox with models of Horseshoe crab In spite of its hard shell and claws, the horseshoe crab is not a crab at all, but is actually more closely related to scorpions and spiders. These “living fossils” belong to the phylum Arthropoda(jointed limbs) and have changed very little in the past 450 million years, surviving several major extinction events. Due to their superficial resemblance to trilobite fossils, scientists once believed that horseshoe crabs were the evolutionary descendants of trilobites. However, several structural differences including the horseshoe crab’s lack of calcite lenses in their eyes excludes them from

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Term
Spring
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Sula, Neal Immega, Mosasaur Tooth

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